v0.10.5

v0.10.5: fix the badges coverage-artifact name so CI goes green

Fixes the badges job, the last thing keeping CI red.

- The v0.10.3 migration set the code job's coverage_artifact to
  coverage-percent.txt, but the badges job downloads the coverage artifact under
  its default name coverage. The two never matched, so once the code job went
  green (v0.10.4) the badges job failed with "Artifact not found for name:
  coverage". Removed the explicit coverage_artifact so the code job and the
  badges job both use the shared coverage default. coverage-percent.txt stays the
  file name inside the artifact.